is an auto manufacturer and constructor of racing cars from England
. The company was founded in January 1997 by amateur drivers and engineers Mick Hyde
and Phil Abbott
, who built open-cockpit sportscars which could be registered for road use and run on a track without modification. Although most of Radical's sportscars are road legal, they also build some purpose-built racing cars, such as the SR9 Le Mans prototype
The company's first car, the 1100 Clubsport, was based on a Kawasaki motorcycle
engine placed inside a small open-cockpit chassis which could house two adults. The cars were intended to run in the 750 Motor Club
's races under the Sports 2000
category, with co-founder Hyde driving.
In 1999, Radical had built enough 1100 Clubsports that they decided to create a one-make series based around the car. Backed by the British Racing and Sports Car Club, the series featured identical cars that were open to anyone who owned an 1100 Clubsport. The same year, Radical debuted their second model, the Prosport. Available with Kawasaki or Suzuki engine up to 1500 cc in displacement, the Prosports were even more powerful and faster than the Clubsports, and even included an adjustable rear wing. The cars were also brought to the United States for the first time, for use in the SCCA D-Sport class in 2000.
Radical's next creation was the SR3, a car which could compete in international racing, such as the FIA's C3 class. The car uses a Suzuki-based engine tuned by Powertec engine which offered 1300 cc or 1500 cc versions and a maximum of 252 hp (187 kW) in the latter. A six-speed sequential gearbox was developed specifically for the car to improve performance. The SR3 could also be road legal in the United Kingdom with the addition of turn signals, a hand brake, a catalytic converter, and road legal tires.
In 2006, Radical would make it's largest leap into motorsport with the development of the SR9, a complete Le Mans prototype which fit into the LMP2 class. Official partner Rollcentre Racing would debut the car with success in the Le Mans Series and 24 Hours of Le Mans.
Radical was able to move into the CN class of cars, used in VdeV and hillclimbing events throughout Europe, in 2007. The SR5 was based around a Honda VTEC 2.0 L engine which could produce 237 hp, although a Ford Duratec was also available.
Radical currently sells six different models, all of which can be converted to street use in certain countries except for the SR9. Various options, most notably in the powerplants, are available on all of the cars.
The most popular Radical model, over 300 SR3s have been built in Clubsport, Supersport, and Tracksport models. The car is built on a spaceframe chassis, and uses a variety of Powertec-tuned motorcycle engines for power. Turbocharging is also available on the motors for even more power.Base versions produce 252 HP and get the SR3 to 60 mp/h in just 3.2 seconds and on to 156 mp/h.
Although this car shares most of the engine and powertrain from the SR3, the SR4 features all new bodywork and undertray, including a front diffuser, in order to make it a more capable track car. Also widely used in various national racing series. This car replaces the initial 1100 Clubsport.
Built for international competitions, including hillclimbs and endurance events, the SR5 features either a Honda
production four-cylinder engine. A variety of gearboxes are also available, with either a manual or pneumatic semi-automatic. The spaceframe chassis does not integrate the engine as a stressed member in an attempt to increase it's endurance capabilities.
The replacement for the original Prosport, the PR6 is a purpose-built race car designed to meet SCCA
regulations. The PR6 features a single-seater cockpit, with many aerodynamic elements from the SR4 added. The PR6 is powered by a variety of motorcycle engines based on class regulations.
Based on the SR3, the SR8 is a more extreme version intended for street and track use. The SR8 also features the largest engine Radical has ever put in their road cars, with the 2600 cc Powertec RPA
V8 constructed by combining elements of Suzuki
inline-4s, and producing 363 hp. A further variant, known as the SR8LM, increases the engine to 2800 cc and brings power output to 455 hp. The standard SR8 currently holds the lap record (6 minutes, 55 seconds) for road legal cars at the Nürburgring
Radical's first Le Mans Prototype
, the SR9 is built to full LMP2 regulations. It is able to be run in the American Le Mans Series
, Le Mans Series
, and 24 Hours of Le Mans
. Engines include a Judd
XV675 3400 cc V8 or a turbocharged Advanced Engine Research
(AER) P07 2000 cc Inline-4. Using the first carbon fiber monocoque
in Radical's history, the SR9 weighs a mere 775 kg. Radical is also investigating plans for upgrading the SR9 to be able to run in the larger LMP1 class.
In early 2008, Eco Racing announced it would run a Radical SR10 in the LMP1
class at the 12 Hours of Sebring
. The Radical is fitted with a AER
bio-diesel engine. The chassis is an upgraded SR9
. The team traveled to the United States, but was unable to run the car due to homologation issues with the monocoque in regards to the car's crash test certification. The car was then entered in the Petit Le Mans
but was withdrawn as well.
Although Radicals started out competing in existing events, it was Radical's creation of their own series that have been the choice of competition for most Radical owners. Radical currently backs four international series, while a further six series have been created on the national level.
The largest and newest series, the Radical European Masters, is a support event for all Le Mans Series races. All Radicals (except the SR9) are eligible to run, with each model running in their own respective class. Two smaller series are the Radical UK Cup for all models of Radical and the Radical Club Cup specifically for SR3, SR4, PR6 and Clubsport models. In Europe, Portugal, Spain, Germany, Sweden and Italy all hold their own national championships with a variety of Radical models. A Middle Eastern series, the Gulf Radical Cup, operates as a pan-Gulf championship for Radical owners at the Dubai Autodrome, Bahrain International Circuit and from 2010 at the new Yas Marina Circuit in Abu Dhabi. In the USA, there are two Radical race series, the Radical Cup West and the Radical Cup East.
In the second quarter of 2005, the company announced its plans to race in the LMP2 class of the Le Mans Series
with their new SR9. The British Rollcentre Racing team would run the first chassis using Judd power before being joined later in the season by a factory team, known as Team Bruichladdich Radical
, who used the AER powerplant. Both teams would score their only points of the season at Nürburgring
, with Rollcentre taking third in LMP2 and Radical finishing in fifth.
Rollcentre would also run the company's first entry in the 24 Hours of Le Mans. Although the car finished in a distant 20th place, the car was able to prove its reliability by being able to finish only months after being completed. The factory Radical squad also flew to the United States for the final round of the American Le Mans Series, where they joined the third SR9 completed, now owned by Van der Steur Racing. However, both cars suffered problems and failed to finish.
For 2007, Rollcentre sold their SR9 as they moved onto a new LMP1 Pescarolo. Embassy Racing purchased the car and continued running it in the Le Mans Series alongside the factory Radical, while Van der Steur would run a partial schedule in the American Le Mans Series. For 2008, Italian team World Racing Cars purchased the Judd-powered SR9 from Embassy.